Electric lock



Aug. 13, 1929. P.R.FORMAN 1,724,457

' ELECTRIC LQCK Filed Dec. 17, 1927 2 Sheets -Sheet 1 F1. Z 1 W3 9 g-n memtoz fir/ R Ewnqn 53 i moi/" s Patented Aug. 13, 1929.

PATENT OFFICE.

UNITED STATES PARIS R. FORMAN, OF RAHWAY, NEW JERSEY, ASSIGNOR T0 NATIONAL PNEUMATIC COMPANY, OF NEW YORK, N. Y., A CORPORATION OF WEST VIRGINIA.

ELECTRIC LOCK.

Application filed December 17, 1927. Serial No. 240,83.

This invention relates in general toelectric looks as applied to vehicles.

One of the objects of this invention is the provision of a new and novel form of electric lock provided with two armatures, one of which is arranged for preventing the operation of the lock, and the other is for short circuiting a portion of the magnet winding of the lock.

A further object of this invention is the provision of an electric lock having a magnet coil'with two portions arrangedso that the lockingv means is actuated first and a switching means is operated when a predetermined voltage has been impressed across the portion of the coil in circuit to connect the other portion in series with the first portion across the circuit. y

A further object of this invention is the provision of an electric lock for vehicles connected in circuit with the axle generator of the vehicle to prevent the operation of the look when the vehicle is in motion.

A further object of this invention is the provision of a lock of the above type having manual means for operating it when the magnet of the lock is deenergized and additional manual means for operating the look by a vehicle attendant whether the vehicle is in motion or not.

These and many other objects are secured by means of this invention.

This invention resides in the combination, construction, arrangement, relative location of parts and circuital connections, all as will more fully appear hereinafter.

Referring to the drawings,

Figure 1 is a front elevational view of the lock of this invention with the cover removed.

Figure 2 is a vertical cross-sectional view of the lock taken on the line 22 of Fig. 1.

Figure 3 is a cross-sectional view of the lock taken on the line 33 of Fig. 2.

Figure 4 is a cross-sectional view of the lock taken on the line 14 of Fig. 1.

Figure 5 is an enlarged side elevational View of a detail showing the relative arrangement of the magnet and armatures, and

Figure 6 is a diagrammatic illustration of the circuit connections.

In the operation of vehicles such as trains, subways, street car lines, elevated lines and the like, it is desirable to have some form of look ,on the doors of the vehicle so that they may not be opened when the said vehicle is in motion, otherwise if the doors are .free to be opened by the passenger it is possible that injury may result by reason of the fact that the passenger attempts to alight before the vehicle has come to rest. By means of this invention electric locks connected to the axle generator of the vehicle are applied to the doors so that when the vehicle is in motion the locksare energized to prevent their operation by passengers. As-is well known vehicles of the modern type are provided with generators driven from their axles for supplying electric current. for various uses thereon. The device of this invention 15 connected in circuit with these generators .so that as soon as the vehicle begins to move the lock is operated to prevent the withdrawal of the lock bolt.- Devices of this general type have been proposed before but they have found little application because it has been found that the lock magnets rapidly overheat when the vehicle is in rapid motion. By means of the present invention this is eliminated by constructing the magnet coil in two portions and providing a switch operated by the magnet for connecting both portions of the magnet in series when the vehicle has reached a predetermined speed. In general, it may be said that for vehicle speeds up to ten miles per hour the actual voltage generated is about one volt per mile. It is desirable after the vehicle has reached a speed of three or four miles per hour that the doors be locked. By constructing the coil in two parts so that one portion only is in circuit with the generator sufiicient magnetic flux is produced to operate an armature which engages with the bolt to prevent its withdrawal. When the vehicle has reached a predetermined speed, for instance, the point where the generator is producing a pressure of 25 volts, the second armature which operates a switch is attracted to the magnet to connect the second portion of the magnet winding in series with the first portion. These combined portions of the winding are adapted to operate under the maximum pressure generated when the speed of the vehicle is a maximum without overheating. To secure these results the locking armature may be mounted closer to the pole piece of the magnet and the switch operating armature may be mounted further away so that the locking armature will be the switch operating armature is not attracted by the magnet until the vehicle is moving at such a speed that the generator is producing a predetermined voltage as, for instance, 25 volts. ent air gaps between the magnet pole piece and the armatures bne armature may-be heavier than the other which is true, for instance, in connection with the armature which operates the switch by reason of the switch parts attached'thereto.

For a better understanding of the invention reference is made to the drawings in which the electric lock casing-is shown at 1. This casing may be constructed of any suitable material such as, for instance, aluminum. A series of holes 2 are provided in the casing for purpose of ventilation. A removable cover 3 is provided for the casing having anopenin'g-4through which a key may be inserted for operating the lock independently of the-magnetic control 'mearis. Rotatably mounted in=the cover is ashai't "5 adapted tobejrotated' by means of the handle 6 and having a notched end 7 for a purpose to be described later. Mounted within the casing land attached thereto'by means of abolt .9 is an electro magnet 8 provided with an insulating end piece 10. The magnet core is provided with the pole piece 11'. Three terminal clips 12, 13 and 14 are mounted on the insulating member 10.- A U-shaped magnetic member 15 encircles the magnet to provide a magneticcircuit therefor and has formed on one end the brackets 16 on which are pivotally mounted the armatures 17 and 25. On the armature 17 is supported a block of insulating material 18 which in turn supports the contact 19 connected through the wire 20 to the terminal 13. Another block of insulating material 21 is mounted on the casing 1 and supports a contact 22 which cooperates with the contact 19. The insulated wire 23 connects contact 22 with the terminal 14. The armature 25 is provided with a right angle projection 24. Within the casing is mounted a supporting plate 26 on which the rotatable post 27 is secured. This post 27 is provided with a shoulder 28 which when engaged by the projection 24 of the armature 25 prevents the rotation of the post. The'post is also provided with an arm 29. Rotatably mounted on the support 26 is a second post 30 having the projection 31. Formed integral with the support 26 is a barrel 32-within which the bolt 33 is slidably mounted. A bar 34 is mounted on the bolt to slide with it and this structure moves to the left of Figure 1 against the action of the spring 35. When the cover is applied to the casing the notched end 7 of the shaft 5 engages in a notch on the upper end of the rotatable post Instead of having differ-- serted through the opening 4 of the cover and engaged with the post .30 may be used to withdraw the bolt whether the magnet is energized or not.

Referring to Figure 6 the magnet 8 is shown'as comprising the windings 8 and 8 connected to the terminals 12, 13 and 14. Terminal '14 is'connected through the wire 23 to the contact 22 and also connects through a fuse and a'suitable switch 81 to one terminal of the axle generator 83. The other terminal of the generator is connected by the wire 84 to the terminal 12. Terminal 13 is connected-by the wire 20 to the contact 19. As will be apparent from the foregoing description when the i vehicle first starts and the" generator is producing a low voltage armature 25 will be attracted by" the pole'piece 11 of the magnetto cause the arm"-24 to engage with the shoulder. 28 to prevent the rotation of the post 27; When thevehicle has reached a predetermined speedsuch as, for instance, a speed at which the-generator produces a pressure of 25 volts the armature 17 will. be attracted by the polepiece 11 to break the circuit between the contacts 19 and 22 so that the winding 8 which has been'shortcircuited will be connected in series with the winding 8 across'the terminals of the generator. With' these two windings in series the magnet is capable of withstanding the maximum voltage which will be produced by the generator. I It may be pointed out for sake of clarity that the device is normally supported in the position shown in Figures 1 and 2 so that the two armatures are normally down. In this position of the armatures arm 24 is out of engagement with the shoulder 28 and the lock bolt may be withdrawn by means of the handle 6. Likewise the eontacts 19 and 20 are together so that the coil 8 is short-circuited. It will be apparent from Figure 1 that the lock bolt may be withdrawn when the post 30 is retated whether the magnet is energized or not.

From the foregoing disclosure it will be apparent that I have devised a new and novel form of vehicle lock which is particularly adapted for practical application. I am well aware that changes in the details of construction and relative arrangement of parts will occur to those skilled in the art without departing from the spirit of this invention and I do not desire, therefore, to be limited except as required by the appended claims.

What I seek to secure by United States Letters Patent is:

1. In an electric lock for vehicles the combination with a double coil magnet, of two armatures for said magnet and a lock bolt adapted to be held against normal operation by one of said armatures when the magnet is energized and the other armature being arranged to control a circuit.

2. In an electric lock for vehicles the combination with a double coil magnet, of two armatures for said magnet and a lock bolt adapted to be held against normal operation by one of said armatures when the magnet is energized, the other of said armatures being connected in circuit with said double coil magnet so as to short-circuit one of said windings when unattached by said magnet.

8. In an electric lock the combination with a double coil magnet and lock bolt having manual actuating means, of means for locking said bolt against operation by said manual means when the magnet is energized and means actuated by said magnet for cutting one of said windings in or out of circuit.

4. In a vehicle having a plurality of doors thereon the combination with a lock for each door, of magnetic means for locking said doors when the vehicle is in motion and means for short circuiting a portion of the magnetic means when the vehicle has slowed down to a predetermined speed.

5. In a vehicle having a plurality of doors thereon the combination with a lock bolt for each door, a two coil magnet adjacent said bolt, of an axle generator on said vehicle connected to said magnet, means operated by said magnet for maintaining the bolt in locked position when the vehicle is in motion and means operated by said magnet for cutting out one of said coils when the vehicle is traveling below a predetermined speed.

6. In a vehicle having a plurality of doors thereon, the combination of a lock bolt for each door and means for manually operating said look when the vehicle is at rest, of a two coil magnet adjacent said bolt, and two armatures mounted to be actuated by said magnet, one of said armatures operating to prevent the withdrawal of said bolt when the magnet is energized and the other armature being arranged to short circuit one of said coils when the voltage supplied to the armature falls below a predetermined value.

7 In a vehicle door safety lock the combination with a vehicle having doors thereon and an axle generator, of means connected to the generator for locking the doors when said Vehicle is in motion and means operative when the vehicle has reached a predetermined speed for connecting a coil in series with said means for locking the doors to prevent overheating of said means.

8. In a vehicle door safety lock the combination with a vehicle having doors thereon andan axle generator, of means including an electro magnet having two windings connected to'the generator for locking the doors, said means being rendered operative while the vehicle is in motion to lock the doors and means operative when thevehicle has reached a predetermined speed for connecting the two windings in series to prevent the overheating of the magnet.

9. In a look, a latch bolt, a handle for operating said bolt, means for holding the latch bolt in normal position, elect-r0 magnetic means including two windings in series for preventing the movement of the latch bolt by said handle when energized and means for short circuiting one of said windings when the magnet is deenergized.

10. In an electrical lock for vehicle doors, the combination with a locking bolt, of elcctrical means controlled by the vehicle movement for maintaining said bolt in locking position while the vehicle is in motion and means for preventing said electrical means from being damaged by an excess of electrical energy when the vehicle has attained a predetermined speed without rendering said electrical means inoperative.

11. In an electrical lock for vehicle doors the combination with a locking bolt, of electrical means controlled by the vehicle movement for maintaining said bolt in locking position while the vehicle is in motion and means for inserting electrical reactance in series in the circuit controlling said electrical means when the vehicle has attained a prcdetermined speed, and retaining said reactance therein as long as said predetermined speed is excelled.

In testimony whereof I have hereunto set my ;iand on this 13th day of December, A. D. 192

PARIS R. FORMAN. 

